Hello crochet friends!

I'm almost done making blanket, but as I lay it out to admire my work... Horror strikes! It looks like my tension became looser as time passed...

I've never made a blanket before, and have read that blocking is a standard step to even out ones work. But... This looks really bad. The bottom right corner is 10cm longer than the top right.

Will blocking save my work and allow me to shape it into a rectangle?